In order to increase the resource usage and redundancy within network systems, multi path connections have been introduced as a way to provide network nodes with the possibility to communicate, that is, transmit and receive data, with other network nodes over several communication paths. The communication paths may constitute connections over different interfaces or Radio Access Technologies, RATs, such as one path over a 3GPP network and another path over a non-3GPP network such as for example Wi-Fi. The provision of multiple paths connecting different network nodes enables the network nodes to simultaneously transmit data packets over several paths. This in turn enables the network nodes to distribute the load on all interfaces connecting the nodes and also to perform congestion control separately for the different interfaces used.
A particular example of a multi path connection is provided by the Multi-Path Transmission Control Protocol, MPTCP. The main principle of MPTCP is to aggregate a set of TCP connections over, for example, different wireless interfaces such as 3GPP and Wi-Fi. It may also aggregate a set of TCP connections over different but simultaneous 3GPP accesses. MPTCP can be described as having one main flow and multiple subflows. Network nodes that are MPTCP enabled and have established an MPTCP connection can therefor communicate over several interfaces simultaneously. This leads to faster communication between the nodes and as such provides for a more satisfied end user.
Other benefits of MPTCP are that:                It allows a single data-connection to use several interfaces simultaneously increasing the throughput.        It allows fallover from one interface to another, e.g. in the case of mobile client moving between 3GPP and Wi-Fi        It increases the bandwidth due to resource pooling.        It is backward compatible i.e. it falls back to TCP as needed.        It is transparent to applications. i.e., the applications benefit from MPTCP without any code changes as they use a standard socket API.        
Notwithstanding the obvious positive aspects provided by multi path connections the relative complexity of the technology, displaying several connections instead of a single connection, make the system slightly vulnerable. The technology is in particular sensitive to scenarios where links or connections begin to malfunction or are disabled/disconnected. If a certain connection malfunctions or gets disconnected, the data intended to be transmitted on the connection may not reach the intended recipient while other data transmitted over other paths in the multi path transmission will. A particular way to address this is to retransmit the data packets that were intended to be transmitted on the malfunctioning path over some of the remaining paths. This however leads to the head of line blocking problem where the data packets to be retransmitted are positioned last in the data transmission buffer of the remaining path. Hence the data packets will be retransmitted after the data packets allocated to the remaining path have been transmitted. This will in turn lead to the unwanted feature of bursty transmissions.